Google just published business listing quality guidelines for local search.
Warning: The new guidelines mean a crackdown’s a comin’. Whenever Google issues new guidelines, it’s their way of saying “quit screwing around”. So if you’re doing anything shady to gain a higher ranking in the local search results, this is a good time to mend your ways.
A few tactics you’ll want to stop, right now:

1. Review spam. If you’ve been getting every friend, relative and literate pet to write a review of your business and then cut-and-paste it to Yelp, Yahoo!, Google Maps and YellowPages.com, stop now. This fits any definition of ‘manipulation’ you might want to apply. If you keep doing it, I won’t want to hear you weeping about Google’s cruelty later on.
2. Duplication. Don’t start listing your business under every dba (doing business as) name you’ve got.
3. Duplication, 2. This is a direct quote from Google: “Service area businesses, for example, should not create a listing for every town they service.” and “Likewise, law firms or doctors should not create multiple listings to cover all of their specialties.” You have been warned.
4. Content spam. If you’ve been tweaking your company name from “Ian’s flowers” to “Ian’s Seattle Flowers in Seattle”, you’ll want to use your real business name from now on.

Trust me. I am, in this business, an ancient, creaky old man. My right knee always hurts when Google’s about to crack down on one abuse or another, and it’s achin’ now…
Related articles: I’ve previously written about local search optimization and adding your address, and how to move up in local search listings.
Matt McGee has a great post about this, too.